Raymond L.S. Patriarca, who reputedly rose from small-time bootlegger to ruler of organized crime in New England, died of a heart attack yesterday in the emergency room of Rhode Island Hospital, Providence. He was 76.

Dr. John Gridley, attending physician on emergency duty, said Patriarca was pronounced dead of cardiac arrest at 1 p.m., despite intense efforts for an hour-and-a-half to restore his heartbeat.Patriarca was taken to Rhode Island Hospital in a Fire Department Rescue Squad ambulance from an apartment on Douglas avenue, North Providence, a few miles from Patriarca's residence in Johnston.

A North Providence firefighter would say only that the Rescue Squad received an emergency call shortly before 11:30 a.m. to go to the Douglas avenue address. Fire and police officials were not available for comment last night, and it could not be immediately determined who lived in the apartment.

Two women who answered the door there refused to identify themselves to a reporter from the Providence Journal.

Gridley said Patriarca had no blood pressure or pulse when he was brought in, and a team of doctors and nurses could not restart his heart despite electrical shocks and implantation of a cardiac pacemaker.

In a business where violent death is often inevitable, Patriarca died relatively peacefully, unable to outwit failing health caused by a heart condition and diabetes that led to amputation of a gangrenous toe.

He had been classified as a criminal for 59 of his 76 years.

In private, Patriarca and his confidants referred to their organization as "La Cosa Nostra" and acknowledged while FBI agents eavesdropped through a "bug," a tiny microphone hidden in his Providence office, that the national syndicate was composed of "families" in major cities.

"In this thing of ours," Patriarca once told an associate while under electronic surveillance, "your love for your mother and father is one thing; your love for The Family' is a different kind of love."

He was described by the Justice Department last Sept. 19 in an indictment returned against Gennaro J. Angiulo of Boston, Angiulo's four brothers and two other defendants, as the head of a "racketeering enterprise." The indictment also referred to the "Patriarca Family of La Cosa Nostra," in which Gennaro Angiulo was described as the underboss to Patriarca.

The indictment, on which Angiulo and the others are scheduled to go on trial Sept. 24, alleged that the business of the "enterprise" is the making of money by illegal means, primarily gambling and loansharking.

Despite the tremendous amount of power and ill-gained wealth attributed to him by law enforcement officials, Patriarca lived modestly, spending his healthier days in the neighborhood of his youth on Federal Hill in Providence.

There, behind an ordinary-looking storefront on Atwells avenue, the man who was known simply as Raymond by friend and foe allegedly directed the vast resources of the New England crime "family."

As he frequently lived, he died under suspicion of murder. He was under indictment in two gangland executions which he allegedly ordered, one dating to 1965 and the other to 1970.

He was also under indictment on labor racketeering charges but was too ill to be scheduled for trial in Miami with four other men. Patriarca and the others were charged with conspiring to seize control of the insurance business of the Laborers International Union in the Northeast.

The tape-recorded conversations in Patriarca's office, actually shop talk, demonstrated his awesome power, the violence he could bring and the political corruption he and his associates could buy in legislative halls.

Patriarca's bugged conversations with the underbosses of organized crime indicated how he was able to influence the decisions of prosecutors, bribe police officials for intelligence information and affect government decisions on granting licenses, probation and parole.

The transcripts of the FBI's tapes also presented a sordid story of violence - how murders were carried out, how delinquent loanshark victims were beaten, how banks were robbed and how legitimate sports activities were fixed.

The bug was planted in Patriarca's office illegally, and the results could never be used to prosecute him, although orders for the installation came directly from the Attorney General's office in Washington as a means of obtaining intelligence information. Law enforcement officials had expected that Patriarca's power would diminish because of his carelessness and lack of security in his office, where he operated National Cigarette Service and Coin- O-Matic Distributors, a vending machine and pinball business.

But Patriarca's power, which he began building in the late 1940s, reportedly remained firm.

He was born in Worcester on St. Patrick's Day, 1908, the son of Eleuterio and Mary Jane (DeNubile) Patriarca. He was 3 when the family moved to Providence, where his father opened a liquor store. Their home was on Atwells avenue, across the street from where Patriarca was to spend the greater part of his business life.

At 17 he was sentenced to jail for a liquor law violation, and four years later he was in state prison with a record for conspiracy to murder, armed robbery, violating the White Slave Act, adultery, auto theft and breaking and entering in the night-time.

Patriarca was 30 when he was sentenced to three to five years in state prison for carrying a gun without a permit, possession of burglar's tools and the armed robbery of a Brookline jewelry firm. It was the start of his involvement in political corruption.

He was in jail only 84 days when the Massachusetts Executive Council, without advance notice to the State House press corps, approved his pardon petition. He was freed and hustled over the state line into Rhode Island before the sun set.

The petition had been handled by Councilor Daniel H. Coakley, a disbarred lawyer, who was to be impeached as a result of his involvement in the Patriarca case and several other matters.

Ironically, 30 years later another executive councilor, the late Patrick J. (Sonny) McDonough, would find himself in an awkward position after FBI agents photographed a meeting in Boston between Patriarca and McDonough. The FBI said the two discussed the possible parole of two Patriarca associates.

In 1939, Patriarca married Helen G. Mandella, a nurse and the sister of an assistant messenger in the office of the late Leverett Saltonstall, who was then governor of Massachusetts and was to become a United States senator. Mrs. Patriarca died of cancer in 1965, leaving one child, Raymond J. Patriarca, who is known as Junior.

Patriarca later married Rita O'Toole, a former hostess at a Rhode Island nightspot. After his second marriage, Patriarca moved from the family home on Lancaster street, Providence, to Golini Drive, Johnston, where he lived at the time of his death.

He commuted daily to his office on Atwells avenue, where he operated his vending machine business and met frequently with key associates. On sunny days, he stood outside the office, puffing on a cigar and closely watching passersby, trying to detect any surveillance.

He scowled at strangers and those out of his favor, and he cursed newspapers, the FBI and the late Robert F. Kennedy. Publicly he denied that he was part of organized crime.

Patriarca's wardrobe usually included a sweater and white socks. Friends said he drank little or no liquor. He was rarely seen socially.

He was imprisoned in 1969 for conspiracy to murder William (Willie) Marfeo, who was killed by four shotgun blasts in the telephone booth of a Federal Hill restaurant in 1966.

Marfeo allegedly defied Patriarca, and so Patriarca reportedly called upon a strong-arm man, Joseph Barboza Baron, a tough ex-boxer from New Bedford who rose quickly in the organization. Baron claimed he killed at least 40 persons.

Baron was picked up in Boston on a gun-carrying charge, and while he was jailed two friends started collecting bail money. They were robbed of $70,000, and Baron realized that organized crime had no interest in his problems.

So, Baron turned government witness and testified against the Patriarca organization, only to meet a violent death himself on the West Coast in 1975.

Patriarca was sent to the Federal Penitentiary in Atlanta, in March 1969, for conspiracy to murder Willie Marfeo. He was serving that sentence when he received a 10-year term in Rhode Island for conspiring to murder Marfeo's brother, Rudolph, and Anthony Melei, who were killed with a sawed-off shotgun April 20, 1968, in a small Providence grocery store.

When he completed his federal sentence, Patriarca was transferred to prison in Rhode Island in April 1973 and was paroled Jan. 9, 1975. He resumed his activities on Atwells avenue, and the FBI and Patriarca resumed their cat- and-mouse game.

In 1978, after more secrets became public through the testimony of another informer, Patriarca was implicated in an unsuccessful attempt to assassinate Cuban leader Fidel Castro in 1960.

Vincent (Big Vinnie) Teresa, a mobster turned informant, claimed he was present when the CIA gave organized crime a $4 million contract to murder Castro. Teresa said Patriarca and an associate picked a former Brookline convict, Maurice (Pro) Werner to kill Castro, but the slaying was never carried out.

Patriarca's reaction was typical. He told a reporter who asked him to comment on Teresa's claim: "You people are crazier than he is."

Last Dec. 4, Patriarca was arrested at his Johnston home and charged with ordering the 1965 murder of Raymond (Baby) Curcio, 31, a drug addict who was found shot in a car in the North End of Providence. There were six bullets in the back of his head and neck, police said.

Curcio allegedly had been slain because he had burglarized the home of Patriarca's brother and close associate, the late Joseph Patriarca. A Patriarca friend, Rudolph Sciarra, 56, was accused of providing the guns for Curcio's slaying.

On March 13, four days before his 73d birthday, Patriarca was arrested at his hospital bedside in connection with the 1970 murder of Robert Candos, 30, a bank robber who was reported missing in 1968 and whose skeleton was found 22 months later in North Attleborough.

Patriarca allegedly ordered Candos slain because of rumors that Candos was to testify against him.